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Signal transduction

AP.BIO: IST‑3 (EU), IST‑3.C (LO), IST‑3.C.1 (EK), IST‑3.C.2 (EK), IST‑3.D (LO), IST‑3.D.1 (EK), IST‑3.D.2 (EK), IST‑3.E (LO), IST‑3.E.1 (EK)


Acetylcholine is a neurotransmitter that helps control muscle contraction. This neurotransmitter functions differently depending on which type of muscle it interacts with. For example, acetylcholine promotes muscle contraction in skeletal muscle but inhibits contraction in heart muscle.
Which of the following best explains why acetylcholine leads to different cellular responses in skeletal and heart muscle?
Choose 1 answer: